Tile variants content (#6956)

Content.Shared/Maps/ContentTileDefinition.cs

@@ -40,6 +40,13 @@ namespace Content.Shared.Maps
 
         [DataField("friction")] public float Friction { get; set; }
 
+        [DataField("variants")] public byte Variants { get; set; } = 1;
+
+        /// <summary>
+        /// This controls what variants the `variantize` command is allowed to use.
+        /// </summary>
+        [DataField("placementVariants")] public byte[] PlacementVariants { get; set; } = new byte[1] { 0 };
+
         [DataField("thermalConductivity")] public float ThermalConductivity { get; set; } = 0.05f;
 
         // Heat capacity is opt-in, not opt-out.